With Night VIsion Clipons, I've used illumination about once in last 5 years ...
With thermal clipons, more useful. But if you don't have illumination you can invert. So illumination can save you a few inversions.
But it also depends on the reticle. WIth T3 reticles I have now, if I get another scope, I will not get it illuminated, but only every second major mil mark in the xmas tree is illuminated and I don't think that is worth the $$.
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NV Clipon, steel, 500yds
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Thermal clipon, steel 500yds
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I'm also looking at NF versus L&S for next scope ... and haven't decided yet. The prices on the MK5s are certainly attractive, but I suspect the image through the NFs is clearer. For me the tougher choice is T3 versus DTR reticle ... that will take some more noodling.
NF 5-25x T3 $3,400 (38oz)(15.4) Illum
NF 4-16x T3 $2,800 (30oz)(12.6) Illum
LS Mk5 5 -25x T3 $2,300 (30oz)(15.7) non-illum
LS Mk5 3-18x T3 $1,930 (26oz)(12.6) non-illum
LS Mk6 3-18x T3 $2,500 (24oz)(11.9) non-illum
LS Mk6 3-18x DTRv1 $2,900 (24oz)(11.9) non-illum (Ballistic Reticle for 7.62)
LS Mk8 3.5-25x DTRv2 $5,200 (33oz)(16) illum (upgrade turrets to M5c2 $250 (Ballistic Reticle for .300WM)
LS Mk8 3.5-25x T3 $3,400 (33)(16) non-illum
But this next scope ^^ is not really for hunting ... don't need all that for hunting.